immune response

American  

noun

1. any of the body's immunologic reactions to an antigen.

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immune response British  

noun

1. the reaction of an organism's body to foreign materials (antigens), including the production of antibodies

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immune response Scientific  

/ ĭ-myo̅o̅n′ /

1. A protective response of the body's immune system to an antigen, especially a microorganism or virus that causes disease. The immune response involves the action of lymphocytes that deactivate antigens either by stimulating the production of antibodies (humoral immune response) or by a direct attack on foreign cells (cell-mediated immune response.) An inability to produce a normal immune response results in immunodeficiency diseases such as AIDS.

2. See also cell-mediated immune response humoral immune response

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Etymology

Origin of immune response

First recorded in 1950–55

Example Sentences

See Examples For:

immune response

Keytruda is administered at the same time to help make sure the patient’s immune response activates against the leftover cancer cells.

From MarketWatch ● Aug. 20, 2026

Those include versions that are considered higher dose or “adjuvanted,” which helps trigger a stronger immune response.

From Los Angeles Times ● Aug. 14, 2026

Replimune’s drug, marketed as Tudriqev, is a genetically modified virus that doctors inject directly into tumors, where it is designed to kill cancer cells and trigger an immune response against tumors elsewhere in the body.

From The Wall Street Journal ● Aug. 6, 2026

It’s that saliva that triggers an immune response in humans—and makes us itch long after the mosquito has gone.

From Slate ● Aug. 4, 2026

In a sense, the earth is mounting an immune response against the human species.

From "The Hot Zone" by Richard Preston